How to build a new plugin:
1. Start xcode, create a new "Carbon bundle" project
2. Create the project under build.macosNNproc/variant/MyPlugin
   e.g.  build.macos32x86/squeak.cog.v3/MyPlugin
3. Edit the project settings:
   Header Search Path: /Developer/Headers/FlatCarbon
4. Add the following files:
   ../../../src/vm/interp.h
   ../../../platforms/Cross/vm/sqMemoryAccess.h
   ../../../platforms/Cross/vm/sqVirtualMachine.h
   ../../../platforms/Mac OS/vm/config.h
   ../../../platforms/Mac OS/vm/sqConfig.h
   ../../../platforms/Mac OS/vm/sqPlatformSpecific.h
5. Add the files for your plugin from
   ../../../platforms/Cross/MyPlugin
   ../../../platforms/Mac OS/MyPlugin
   ../../../src/plugins/MyPlugin
6. Cross your fingers and compile

Alternatively, adapt the Template provided here. Be sure to edit VMSRCDIR to be
the directory containing vm/interp.h from the VM you're adding the plugin to.
